1. Field of the Invention
The present invention relates to an LSI design support apparatus and an LSI design support method. More particularly, the present invention relates to an LSI design support apparatus and an LSI design support method used for setting connection relations between substrates.
2. Description of the Related Art
In LSI design, a process of a study of assembly is known in which selection of a package substrate of an LSI, and electrical connection between the package substrate and a chip substrate of the LSI are studied. In the process of the study of assembly, a package substrate of an LSI that suits a chip substrate of the LSI is firstly selected. After that, connection relations, which pad in the chip substrate should be connected to a stitch (or lead) of the package substrate with a bonding wire, are studied. In the description below, the connection relation between the stitch of the package substrate and the pad of the chip substrate is also referred to as “pin-connection”, and processing to set the pin-connection is also referred to as “pin-connection processing”. The pin-connection processing in the study of assembly has been manually conducted so far by designers while looking at CAD (Computer aided design) drawings.
As a technique relevant to the process of the study of assembly, for example, an LSI assembly design support system is disclosed in Japanese Laid Open Patent Application JP-A-Heisei 7-152811. FIG. 1 is a block diagram showing a configuration of the LSI assembly design support system. The LSI assembly design support system determines electrical connection between pads and an LSI package, and determines each pad to be electrically connected to an external pin of the LSI package for each LSI package into which a chip is installed. The LSI assembly design support system includes: (A) a chip-data input means 102; (B) an LSI-package-data input means 103; (C) an external-pin electrical-properties specifying means 104; (D) a pin-connection means 105; (E) an assembly check means 106; (F) an electrical-properties check means 107; an interface section 101; and a memory section 108. The chip-data input means 102 supplies data of an external form of an LSI chip, pad coordinates, and conditions of electrical properties which the pad can have. The LSI-package-data input means 103 supplies data with respect to an LSI package into which the chip supplied by the chip-data input means 102 is to be installed. The external-pin electrical-properties specifying means 104 specifies electrical properties of the external pins of the LSI package supplied by the LSI-package-data input means 103. The pin-connection means 105 specifies electrical connections between the pads of the chip supplied by the chip-data input unit 102 and the LSI-package-data input means 103, and the external pins of the LSI package. The assembly check means 106 checks whether the electrical connections specified at the pin-connection means 105 satisfy assembly conditions in actual assembly processing of the chip and the LSI package. The electrical-properties check means 107 checks whether the electrical properties of the pads of the chip can be the same as those of the external pins of the LSI package connected through the electrical connections specified by the pin-connection means 105.
In the case of the LSI assembly design support system of the above related art, a worker performs assembly design for an LSI package on a dialogue basis while specifying connection between each external pin of the LSI package and each pad of a chip, at the pin-connection means 105. Such design requires that setting of a connection relation between the external pin of the LSI package and the pad of the chip through a wiring all be conducted by manual work. Therefore, the heavy burden is imposed on the worker, requiring a great number of man-hours. As a result, long working time is necessary. In particular, the number of pads and the number of pins of a package are increased with the miniaturization of pad pitches. Therefore, the worker needs to conduct an enormous amount of pin-connection processing manually, causing the heavier burden on the worker. A technique is desired which is capable of reducing the work burden on the worker, working man-hours, working time, and manufacturing time.